SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8924bdad951301bcb87ca3916762428d9368dc237038ef76fb366b8b63cbb2d3' 
  AND token = 'e4Nt5or5SyuLzSNdz7Nxg+OPZpQEsgltBjg1z0IoTg8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}