SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70ff4db8c4c7f39b39f92dd460c4f71cfaa0f1e23347e52d9e7d30f630820588' 
  AND token = '+PJYvrCeO9nCmqcrkVZU3vO9MQuj7FmgcR802+JzpmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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