SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a2c938506518b6d38f8219996c1b7b30275001eab1af2436439a5cd5bf81722' 
  AND token = 'TV7x07ZKeR56CHYXOZVyCQLSqyR+gJTs6szgAwBbd/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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