SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4a2735892d658a31dc3b3ee8ef77c608db141db82a66c90740cb86452609563' 
  AND token = 'DmGgAPlbXOAKqjvlLBPL2Hx/IGQuq0unSKRhS2P+tLM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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