SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '50233875d87a0498610c6bda7180ea9fc1ac231140ef8cd3e0b7ac3f7064a129' 
  AND token = 'u28Bz/hE4W6zNUM9ALzb6/lvdQHTGv7ePTVZXSrnnYE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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