SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24d487293309cae34c8e30c80a6f90e57a6d90bbf6054e0514c1266a7ce73dd7' 
  AND token = 'sasSaivDCGEfTOL81uF5yKDNmZohywdD20dRAhJDtDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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