SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '42f33d0ddf0267ad404e28bd536c701862042bd8e723e9ac983804014bf858fc' 
  AND token = 'ANcYi0+oQqvpN5zapWJb75GXPNkpRHgJeCH2uJFMVYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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