SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f010d39a4b50e7381d732eaaaa3856f4571a3c19896537faf571a9ce71ceb2f3' 
  AND token = 'DYvR8cgzecA+gIppM6atyEXhfdaYTkqeZllYqWaFRyA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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