SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4212fbadf2adbd1c35b1a199179e1ecab5965daf432803bafeaa0e60cf73efd' 
  AND token = 'o6V91crgEd+HSWKv1VvDse1u5ffQ37zeJfExmn60FFc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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