SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9a7325b16d740c709755f59377c2a070204a7f3f6b34f3ff4e3fca453323822' 
  AND token = 'wtlAR5gmxmnAQdCwtP847bDXFe1JcnXHEcZoF0QntwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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