SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc6ca22dd3a874c336c5f95c6b91fce655ae29cae5bbe47536fe3a116852416d' 
  AND token = 'JIKqY5h34PmBrzPTI8hs1FtYxPVYkBDbj2Xw7EBKMOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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