SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4de24ba886f062507fe8acbefbc1db47fa93b39ecd46bc75d866c8ac7dfd85cc' 
  AND token = 'zqcaHRFJdWJIl7hmmwQ5Qw+Tjz5AfVTmhpkHsGC3L/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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