SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd052eebbd69eb19ffc1f6b3106a207f6b7b5a5611109bead443699e921781500' 
  AND token = '0uGvFXbWXoie2vv6pubZOntFdTfXZcbY5+FgtGglnJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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