SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c1875ec87fee440b0ad70da78952149a3a102aa1a1ba2eb4ca6cb1f203191f8' 
  AND token = '17FDPgmZz1IZBQm9EzeGhxujCK1ahZByuU5FGdwoSGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00072

JSON explain

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