SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1800cc8afa08cf1b569818f680fbe16ffea760e5c8a934a13ad8ccdfe671c8d5' 
  AND token = 'NVzLdcbtp4h7ebvLXwXL5gQRE4R4FCHOsDP60JDBqKg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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