SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd874c5565a3e2e5853cd484625bc139351aec14b2c2513a1c5af59dd737ac1d9' 
  AND token = '7kib70i7IAJDfWjYe4J/pyLZe0p7cMLQXLyzrW3IcXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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