SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '541e36035174f57ccfd228e26de5f31d9d878268cac350f8f4cfdf78cf4ee854' 
  AND token = 'T5JP2QHFQ9T0SqwZUc/wEXspFjGnsDv/u99YxlZqmyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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