SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '66ca6107b2f74b69fa4371e8f48f5a2c7e3c30b47ef41a97c62bc1f90de67f25' 
  AND token = 'jK1WTTHgjRJckJZ9X3NPcAGBpL5eiIP/NMayXQJ2/sg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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