SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b512f95d8bf8712f39bec84de4aa3c8e6d127726f6f3e4aa6966b0775411e403' 
  AND token = 'uyxyxZAgp+T5/bOUCflLybfBkFcugy4L58PaVWUSdD4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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