SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f807db92502f646aef6733b96230403fce372d4be63b61fef620073945a982ed' 
  AND token = '9v0lilL4D6GqhJtxXdFCVHG9Lx2w7cBeshPuHm9RVvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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