SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'aacdd5de2167e1f93d7fa05a83161405c6d34039a79f81b9d3bc16408255d1c0' 
  AND token = 'xkIgXbL/5VOkLL8cJguZL+I77LtFBhE99innn55vTPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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