SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ed2c068a0b6733f611e99a73bc482336416e14356f1671dfbe6c68651c7eb8a' 
  AND token = 'gXPf51nEpw+6YdoPtH5iOGv3pIKveVrvoK7KhLT1V2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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