SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b156523384a2e8c15ae7675f419f82bcfa7e9904c37ba48884fcf9b72f2a3d80' 
  AND token = 'MhUSoY3S+rdTNw6OoJQbHS7UPoJRw4Sp8Qo7q4NJrNg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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