SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bae3b2c362ffb517331999346b95ce757a156c95919bcda18d3ef8598543870c' 
  AND token = 'nbvPMCiMqlkDF4LoiiLe+4tIntg5qXWxGmKH2Vg7YBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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