SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a99772d4b9439e46779345463123a017cac2e95e8948690e051f84d07f152d7' 
  AND token = 'bEiPsjZERZWYiC1TAFAvxmpmpjr95Z0vPfyx5M5Q5vs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}