SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70902c6e5c0caaa69e29d3392fa18b64201ce44fd14d89dde2aa2f26cd4c974d' 
  AND token = 'g662CmOviH88SHz+MzhDoL0gDYbZvJBqf4AUCYvHKxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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