SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '086d147d4d3697279507848f2dac67b52bb195a3c5c0b2726694f5786fa63f08' 
  AND token = '1pu/Yf/3tNlVxxv8aLDO8awQOaxYPXAwEHp1r1vmwgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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