SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96c22bd0f9d4ba46aefa33bf90fb6e5daf888c8790aedac4642d37f7bbdb5ef6' 
  AND token = 'kzinyaCFxP196j1/lPio0UNGhncHieEQZZ4dOsv5Jrc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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