SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cf959be2c041774902227c8c3e393d8ac2e8a8ae00d14fdc48c619c16dddd31' 
  AND token = 'dD9ZWUCL5o1P5ULoZFkm1lBqHVR4jEoaWKIbcKuxJBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}