SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82279a9989b7e30e35157871e0ecc13a16468f4d12af4e80f57d0aba9701e2b4' 
  AND token = 'ML+rvFPfYJIXgIO+L1AQ/dbKnxcMQ6JZCwmtLqkZiHI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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