SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c1d15be1eb3553a64da4e8e3ad46aa00f6806bbb1284a70ea9e145985b6f059' 
  AND token = 'PubXwoW31SGCMuzOQN0zn0i8XZ886O5PGKHVO5pQbR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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