SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cfc3593cb19489bd24105bb2b0650e877d40b26fb779a29e2d288084f5ab1eef' 
  AND token = '9pvZjo/rrYjR4jXnq0gq0fHE/gHRNn7ITSunvvC99tw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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