SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ffe325683d8a4241e672ed0b96cce2673ca79c6ad6bd1887d989ca57dab2dfc6' 
  AND token = 'qBjgKJ8rcymhiXwld2XUUEPMZyu7NzjG4jYXlgM8ALo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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