SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f316587190256835c1a15c4b0242f7efb117f2732a1cc3e6cddc31c430b72fac' 
  AND token = 'wwnUj2wTKQCFeyAuSNR1TWAOGyzSRb9AQ9MdkLF14r4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}