SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ccfefe9b46b370dc17e8e340d8973037d33abaa2645bd87e187ba6ce71f9631' 
  AND token = 'HyGPl72Xo4I2Jobg/OJHXKQDMFPGdmAfcevAmUIYeWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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