SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02b52287475645d981ba465eec5027147d1e04c6096c3a0b28b170506b844c14' 
  AND token = 'hRKdhvDSWgLnZAi/KnVHtotdPG16NlyVqUpunEJ5aiI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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