SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16bab90b9914f3c2303701ddea47a1414727d74394a09bfcbc246cec26592863' 
  AND token = '5pJcR6RUnL1AZEDmRN2gKMP0DBLKhkFrCdnGXp0KWnE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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