SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '543c9d3436ad13df161fe21ebe3d734e98d247b90aa1768dbc01633c710e5062' 
  AND token = 'OIrdCWTq4HlbcCMH0WC5Fbwl0Wv/j7myfvwPMHH3fa0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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