SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48d437b9320096a3f3f789d3db4c16a48cd5bd616e88e95966c5d412213d176b' 
  AND token = 'C5H0MAT1wA7ZHTaF8SGgB6dtF5lqtJveVhujWHDRoA8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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