SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '598ba5d7776b030d1891c60ffe11309b0abceb98b09cfa1b1bf8d07a6b27ac95' 
  AND token = 'SakT9FDinYv1M6aFxL+4oOId0fDWipBdifLn+tktu9A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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