SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'daadfadc5fdbb0e62513a3645226bdf72311784ef3d3488a62e3c93a1a509606' 
  AND token = 'yjQCeZfwGnc5DgumS0IkJ6e/l4tlFzNQJK3hbm1NfTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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