SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7ddb93ffb8c483ca823bd09dd7b42be57a1753a073739e86dbd9936d8bd04b6' 
  AND token = 'tnbIumbJ2LO743uSw8m4xdK1mvyPwgD9MR0zu1BrHrY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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