SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd197846d6e8ab95242dcea9845d5695adf2be2c029a4678d64f165313fe5459b' 
  AND token = 'BimrtEHLwIR4clJ+smHqi4uUPBiEJpbimxrDeXNJWo0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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