SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7223047c7f5f4899d4da734f7ab5844950a737b1f353e2014b9b561f3747da0' 
  AND token = 'vGGSQHXF8t6FCmpCOtlHt4y9zjEQTC/g4Mq2QKBlzQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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