SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2214ec7876e33cc60b86503227248c23ab7022b3cc922e38e0fdeac21fafb30' 
  AND token = 'kPMBcdi0Q0eYUy1g/RtEgLtbBMHh0RVhfcbSv6rbaWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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