SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '865adf420273fa4342cc9979517a0d300121b2c17c28442a5c5d899062552dd4' 
  AND token = 'ELuXT2n2R+3j6lHdNyCwVEDMiTfqpNWxgfNW9VlEIDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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