SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efa43ca0a4e616008b421f67f92b0437ee23ee0d884614480a3135af0d6bfda4' 
  AND token = 'IPmMzqabwNsFTg9sZXLdQbZSMu/ZpNkXTycQpiXuz7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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