SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b7dcac586d218bdfad86f3ae030ea8ee80a4fe9c86968ff3a25ef697d3fad134' 
  AND token = 'oI0V1/UklJhDnV2DEbeSqhZf93I7wzEklLT4AXKYJNk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}