SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9453c28af27d8f6bafc42cdde96dcd12c5c75504b4af5685381607ba08a12c9' 
  AND token = 'Gv9D/w49+b+bLIamuqFaJjAdJeSwqhAmVz7/HnEse2U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00133

JSON explain

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