SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7309b0a87b02a970129d3e4adeac6bfd8862c670f4707f4a0968bfdf3a07f612' 
  AND token = 'zFmRXvCGWIgMou3ocvj/H4Xc+whA5fUXfC95BbmyEDY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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