SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '774bcf49690e1b61acd50aad4534f4edc0ec2b9ff7eb491c393e2ed3b67487f5' 
  AND token = 'mUT7W5rO4JC5LmDPbHxScLNst01Ezzgt33USKGIIrhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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